1. Field of the Invention
The present invention relates to a toner replenishing apparatus for replenishing toner to a developing section for developing an electrostatic image on a surface of a photoreceptor, and an image forming apparatus including the toner replenishing apparatus.
2. Description of the Related Art
In a toner replenishment method in an image forming apparatus in which an electrostatic image on a surface of a photoreceptor is developed with toner to form an image on a recording medium, a toner replenishing container is firstly filled with toner. Then, the tonner filled in the toner replenishing container is replenished to a toner hopper and is supplied from the toner hopper to the electrostatic image on the surface of the photoreceptor. In the case of such an image forming apparatus, when a user fills the toner replenishing container with toner, sometimes, there is a problem that a user's hand is contaminated because of toner adhered thereto and the like to complicate a toner filling work.
In order to solve such a problem, recently, a method becomes mainstream, that when the toner to be supplied to the electrostatic image on the surface of the photoreceptor becomes insufficient, but it is determined that the toner in the toner replenishing container is exhausted and the toner replenishing container itself is replaced with a new one. In such a toner replenishing container, the toner is aggregated to one another to be solidified due to weight of the toner, resulting that the toner may not be able to be replenished smoothly to the toner hopper.
In order to prevent the toner in such a toner replenishing container from being aggregated to one another, a rotary toner replenishing container is practically in use, in which toner is guided and transported by a spiral projection formed on an inner surface of the toner replenishing container and then replenished to the toner hopper while rotating the toner replenishing container itself. Such a rotary toner replenishing container is able to suppress aggregation of the toner in the toner replenishing container with the simple structure. However, the rotary toner replenishing container has a problem that toner in the toner replenishing container is adhered to an inner wall of the toner replenishing container and remains unfed from the toner replenishing container.
For coping with such a problem, for example, Japanese Unexamined Patent Publication JP-A 2000-147887 discloses a rotary toner replenishing container provided with a spiral scraping member that rotates along an inner wall to scrape toner adhered to the inner wall thereof.
However, in the toner replenishing container disclosed in JP-A 2000-147887, when there remains large quantity of toner in the toner replenishing container, frictional resistance between the spiral scraping member and the toner increases to increase a drive torque for rotating the toner replenishing container, thus posing a problem that wear of a driving component of the toner replenishing container and the scraping member itself is rapidly progressed.